This invention generally relates to shackles for suspending poultry carcasses from a conveyor line of a poultry processing plant. More particularly, the invention involves shackle assemblies for transporting poultry carcasses in series, suspended by their legs, over a track of a weighing scale for weighing the suspended carcass and then along a cut up line for separating the parts of the carcasses, or otherwise treating the carcasses in response to the detected weight of the bird.
In modern poultry processing facilities, birds, such as chickens, are suspended from shackles on conveyor lines where they are transported sequentially through numerous processing operations. Each shackle includes a pair of stirrups for supporting the feet or legs of the birds and for maintaining the birds in an inverted position. The upper portions of the shackles are supported on a conveyor track and are transported through the processing area by a conveyor chain.
Typically, the birds are suspended by their feet from shackles on a first conveyor line for killing, decapitation, defeathering and feet removal. After the birds have been processed through the kill line, defeathered, and had their feet removed, the carcasses are then rehung by their legs from shackles on another processing line where they are passed in sequence through an evisceration room for removal of the giblets. The birds are next dropped from the evisceration line into a chiller where the temperature of the birds is reduced. The chilled birds are then rehung for conveying through subsequent processing stations, such as a weight scale for determining the weights of the birds and separating the birds according to their weights, and/or through a cut up line where the carcasses are cut into parts.
Some of these conventional poultry processing plants include a weight scale that is placed upstream of the cut up line for weighing the shackled carcasses and assigning different cut up functions for each carcass depending upon its weight. In this configuration, a computer receives the weight information for each shackle from the weight scale. Then, as the weighed shackle approaches a subsequent treatment station, such as a cut up module, the carcass can either enter or bypass the cut up module by using a diverter to deflect the carcass away from the cut up module in order to avoid cutting the carcass.
The shackles that carry the birds through the weighing and cutting line are typically pivotal about a vertical axis for rotating the carcasses to the appropriate angles necessary for the cut up equipment to receive and cut the various parts from the carcasses. Turning shackles suitable for use on a cut up line are disclosed in U.S. Pat. Nos. 5,092,815 and 5,487,700, and in U.S. patent application Ser. No. 09/181,099 which are all hereby incorporated by reference into this document. U.S. Pat. No. 5,366,406 is also incorporated by reference and discloses a angularly displaceable grading shackle with wheels that engage a weighing scale as the shackles are weighed.
Shackles that are currently used for the weighing and cutting lines require the entire shackle and bird to be weighed simultaneously. This is accomplished by moving the conveyor line 180 degrees about a carousel that tilts both the shackle and bird in order to detect the weight of the bird. The weight calculated from such conventional technology is not very accurate because the whole shackle is being weighed instead of just the bird. The requirement for a 180-degree turn about a carousel also requires additional space in the line and is expensive to configure.
Therefore, it would be desirable to provide a shackle for transporting poultry carcasses continuously through a weight scale and along a cut up line that does not require the whole shackle to be lifted during the weighing function and that does not require movement of the shackles and the birds about a carousel. Instead, it would be desirable for the shackle to move straight through the weight scale and include moveable sections that require only a portion of the shackle to be weighed with the bird.
It is therefore an object of this invention to address these and other shortcomings of conventional technology by providing, in various forms, a shackle assembly for transporting a poultry carcass suspended by its legs along a processing path and over a weighing scale track for weighing the carcass. The shackle assembly includes a trolley support, a trolley mounted to the trolley support for engaging the weighing scale track, and a bird carrier for suspending the poultry carcass by its legs. A cam-actuated turning means is mounted to the trolley support and operatively connected to the bird carrier for rotating the trolley support and the bird carrier in unison about a vertical axis. Telescopic connector means telescopically connects the trolley support to the bird carrier and suspends the bird carrier from the trolley support.
The telescopic connector means further includes the trolley support and the bird carrier having overlapping ends with aligned openings extending therethrough, and the trolley having a wheel axle extending through these aligned openings. The overlapping ends of the trolley support and bird carrier are adapted to move axially with respect to each other in response to the trolley passing over the weighing scale. For example, one of the aligned openings may be an axial-aligned slot.
The telescopic connector means includes one of the trolley support and the bird carrier having a tubular support defining a central passage and the other of the trolley support and the bird carrier having a rod extending into the central passage of the tubular support. For example, the trolley support will have a tubular support defining a central passage, and the bird carrier will have a rod extending upwardly into the central passage of the tubular support. The tubular support and the rod define aligned openings wherein the trolley includes a wheel axle extending through the aligned openings for connecting the tubular support and the rod in a substantially non-rotating relationship. At least one of the aligned openings is preferably of larger vertical breadth than a cross-sectional breadth of the wheel axle for permitting vertical telescopic movement between the tubular support and the rod in a substantially non-rotating relationship. Also, the aligned openings of both the tubular support and the rod are of sufficient breadth to permit the wheel axle to tilt when one of the wheels is elevated higher than the other wheel.
The invention also generally relates to a method of processing poultry carcasses as the carcasses move along a poultry processing path and for weighing the carcasses on a weighing scale as the carcasses are moved along the processing path. The method includes the steps of suspending the carcasses from a shackle having a trolley support with a trolley attached thereto, and a bird carrier connected to the trolley support. While the carcasses are suspended, the trolley is passed over the weighing scale, and in response to passing the trolley over the weighing scale, the bird carrier is lifted with respect to the trolley support by the scale. The method also includes weighing the carcass as the carcass passes over the scale, turning the carcasses about a vertical axis, and cutting the carcass into segments.
The step of turning the carcasses about a vertical axis may further include moving the trolley support along the processing path, and engaging a cam follower mounted on the trolley support with a corresponding cam positioned along the processing path. The step of lifting the bird carrier with respect to the trolley support may further include telescoping the bird carrier with respect to said trolley support.